The short answer here is no. The problem is that there is really no distinction between what is and is not personal information.
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Data, data everywhere!
When you’ve been using a computer for a certain amount of time, information that you or I might consider to be personal is distributed in multiple places: in the registry, in data files, in the programs that are installed, and even those programs themselves may save data in completely unknown and non-standard locations.
There is simply no way to know; there's no way to scour the machine, identifying what is and is not personal information or what should and should not be erased.
The nuclear option
The only safe thing to do is to erase the entire machine.
Use a tool like Dban (Darik’s Boot and Nuke) to first completely erase the entire hard disk.
Then, install Windows from scratch. You'll also install the applications that you want to make available to this friend from scratch.
Only then are you really safe.
No installation media?
Now, if you don’t have the installation media, that’s unfortunate.
The solution is to grab a free operating system like one of the Linux distributions and make that available. Or perhaps purchase a copy of Windows to give with the machine so that you do have installation media.
But the bottom line here is that there really isn’t a safe way to give a machine with only "some" of the information removed from it. For safety’s sake, it really is an all-or-nothing proposition.
Wouldn’t there be another option?
If you don’t have the installation media, but your computer happens to have the hidden install partition in tact, it would seem to me that the thing to do would be to use the install partition to reformat and reinstall Windows and whatever else came with the computer from the factory.
For those who are slightly more paranoid, they could connect the hard drive to another computer to reformat the visible partitions (but not the hidden install partition) and then use something the CCleaner to wipe the visible partition. Then, use the hidden install partition to install Windows and whatever else came with the computer from the factory.
Hi Leo, how do I get rid of banking details off my computer? I am using windows ten.
It depends on how you entered the banking details, how they were used, and by what software. There’s typically magical “erase only this type of data everywhere” function, so the article you just commented on is the only sure-fire approach.